In these years, heterogeneous networks (HetNets) have been proposed, in which a plurality of types of radio base stations having different transmission powers (transmission capabilities), such as a macro base station, a pico base station, a femto base station, and a remote radio head, are installed in a multi-layered manner. In heterogeneous networks, a base station having a high transmission power (for example, a macro base station) tends to be selected as the radio connection destination of a user equipment in a cell searching stage or a handover stage compared with a base station having a low transmission power (for example, a pico base station). Therefore, connections from user equipments tend to concentrate on a base station having a high transmission power, causing excessive communication load.
To solve the above problem, Patent Document 1, for example, discloses a technology that controls a communication cell boundary in a variable manner by changing an offset value (correction value) that numerically reduces the power level received by a mobile station, according to parameters, such as the load and the amount of traffic on a radio communication system. The mobile station in Patent Document 1 selects a destination base station (macro-cell base station, micro-cell base station) according to the offset power level (reception power).